Yamaha Grizzly 450 service schedule

1. Park on level ground, remove panel E, start the engine and warm it for a few minutes, then stop it and take the key out.
2. Put the tray under the engine, take out the filler cap, then the drain bolt and gasket, and let it drain.
3. Remove panels C and D and unscrew the filter cartridge with the filter wrench.
4. Put a thin coat of oil on the new cartridge's O-ring, check it is seated, and tighten the cartridge to 17 N·m. Refit panels D and C.
5. Refit the drain bolt with a new gasket at 23 N·m.
6. Fill with about 2.40 L of the right oil and refit the filler cap. Wipe off any spilt oil once the engine is cool.
7. Idle for a few minutes and check for leaks. Stop the engine, wait at least 10 minutes and check the level is between the dipstick tip and the maximum mark, with the dipstick resting in, not screwed in. Refit panel E.
8. Every 5,000 km, 320 hours or 12 months, also have the oil strainer cleaned by a Yamaha dealer.

Tools: Drain tray (4 L), Oil filter wrench (from a Yamaha dealer), Socket set, Torque wrench (17–23 N·m), Funnel, Gloves

1. Let the engine cool, take the key out and remove panel A.
2. Pull off the plug cap and unscrew the plug with the kit spanner.
3. The insulator round the centre electrode should be light to medium tan. A very different colour can mean an engine fault: have a dealer check it.
4. Check the gap is 0.6–0.7 mm and clean or replace the plug as needed.
5. Screw it in by hand first, tighten it as your handbook says, then refit the cap and panel.

Tools: Plug spanner (in the tool kit), Feeler gauge, Wire brush

1. Have a Yamaha dealer check and adjust the valve clearance with the engine cold.
2. The carburettor idle speed and choke are checked on the same schedule.

Tools: Dealer job

1. Park on level ground, engine off, key out.
2. Remove the engine guard and the final gear case guard.
3. Put the tray under the final gear case and remove the filler bolt and the drain bolt with their gaskets.
4. Refit the drain bolt with a new gasket at 22 N·m.
5. Fill with Yamaha Friction Modified Shaft Drive Gear Oil to the brim of the filler hole. Other hypoid oil (SAE 80W-90 GL-5) can make the rear brake noisy.
6. Check the filler bolt gasket, refit the filler bolt at 22 N·m and check for leaks.
7. Refit the engine guard and final gear case guard bolts at 7 N·m.

Tools: Drain tray, Socket set, Torque wrench (7–22 N·m), Oil pump or squeeze bottle

1. Park level, engine off, key out.
2. With the reservoir top level, check the front brake fluid is above the minimum mark. A low level can mean worn pads or a leak; a sudden drop needs a dealer.
3. Check the front brake lever has no free play; if it has, have the system checked.
4. Check the rear brake lever free play is 10.0 mm and adjust the lever, pedal free play and pedal height as the handbook shows.
5. Have the front pad lining checked (wheels off): replace both pads if under 1.0 mm. Have the rear friction plates checked by a dealer.
6. Wipe up spilt brake fluid at once; it damages paint and plastics.

Tools: Torch, Rule, Rag

1. Have a Yamaha dealer inspect the V-belt.
2. After riding through deep water, remove the V-belt case drain plug to let water out. If water comes out, have a dealer check the quad.
3. Empty the V-belt cooling duct check hose (left front) if dust or water collects in it.

Tools: Dealer job

1. Park level, engine off, key out.
2. Wipe each grease point clean and grease the drive shaft universal joint, the rear knuckle pivots and the steering shaft with lithium-soap grease.
3. Lubricate the moving parts and cables, and the throttle cable and lever housing.
4. Wipe off surplus grease so it does not collect grit.

Tools: Grease gun, Rags

1. Park level, engine off, key out.
2. Turn the steering and look all round each axle boot for cracks or splits.
3. Have a split boot replaced before mud gets into the joint.

Tools: Torch, Rag

1. Park on level ground, engine off, key out.
2. Put the tray under the differential gear case and remove the filler bolt and the drain bolt with their gaskets.
3. Refit the drain bolt with a new gasket at 10 N·m.
4. Fill with the recommended oil to the brim of the filler hole (about 0.23 L).
5. Check the filler bolt gasket, refit the filler bolt at 23 N·m and check for leaks.

Tools: Small drain tray, Socket set, Torque wrench (10–23 N·m), Oil pump or squeeze bottle

1. Only open the radiator cap with the engine and radiator cold. Put a thick rag over it and let any pressure out first.
2. Park level, remove panels D and E, put a container under the engine and remove the coolant drain bolt and gasket. Use a trough so coolant does not spill on the footrest.
3. Remove the front carrier and panel B, then the radiator cap. Remove panel C and the reservoir cap, disconnect the reservoir hose and drain the reservoir.
4. Flush the system with clean tap water, then refit the drain bolt with a new gasket at 10 N·m and reconnect the reservoir hose.
5. Fill the reservoir to the maximum mark and the radiator to the top with 1:1 antifreeze and distilled water.
6. Refit the radiator cap, idle the engine for a few minutes, stop it, top up the radiator if low, then check for leaks. Refit the panels and carrier.
7. Coolant is poisonous to animals: catch it all and dispose of it properly.

Tools: Drain tray and a trough, Funnel, Torque wrench (10 N·m), Thick rag

1. Have a Yamaha dealer change the fluid and the master cylinder and caliper seals every 2 years.
2. Have the brake hoses replaced every 4 years, or sooner if cracked or damaged.

Tools: Dealer job

1. Park level, engine off, key out. Remove the seat, unhook the cover holders and take off the air filter case cover.
2. Pull out the element, take off the lock plate and slide the sponge off its frame.
3. Wash the sponge gently in parts-cleaning solvent, never petrol or low-flash-point solvent. Squeeze it out without twisting and let it dry.
4. Replace it if damaged. Oil it with foam air filter oil so it is wet but not dripping.
5. Refit the sponge and lock plate, seat the element properly in the case and refit the cover and seat. Never run the engine without the element.
6. Check the air inlet for blockages and the rubber joints to the carburettor for an air-tight seal.
7. Empty the check hose at the bottom of the air filter case if dust or water has collected in it.

Tools: Parts-cleaning solvent and a tray, Gloves, Clean rag